The present invention relates to an image reader for imaging the optical image of an original image on a solid-state image pick-up device using imaging optical means and for converting such optical image into an electric signal. More particularly, the present invention is directed to a structure for down-sizing such an image reader.
Image readers which are applied to such devices as facsimile machines, digital copying machines and scanners for personal computers include a type such that an original 103 is placed on the upper surface of a frame 101 having a platen glass (not shown) on top thereof to read out images as shown in FIG. 6.
Inside the frame 101 mounted are a light source 105, mirrors 107, a lens 109 and a solid-state image pick-up device (e.g., CCD: Charge Coupled Device) 111. These components constitute a reducing optical system.
Another type of image reader includes, as shown in FIG. 7, inside a frame 101 having a platen glass (not shown), a light source 105, a rod lens array 113 and a contact type sensor 115, all constituting an equimagnifying imaging optical system.
A light beam emitted from the light source 105 is reflected on the original 103 surface and the reflected light is imaged on the solid-state image pick-up device 111 or the contact type sensor 115 through the reducing optical system or the equimagnifying imaging system, respectively. That is, the reflected light is converted into an electric signal in accordance with the light and shade of the original.
According to the aforementioned conventional constitution, a platen glass for placing the original 103 thereon is necessary, which requires the width and depth larger than those of the original 103 on the image reader. Further, the height of the image reader is also restricted by the space for accommodating the reducing optical system or the equimagnifying imaging system; e.g., a height of some 10 to 30 cm must be ensured. Therefore, there is the problem that the image reader becomes large in structure.
Being comparatively large in structure, the conventional image readers are not suitable in being installed on top of a personal desk. Thus, their down-sizing has been required strongly.
Furthermore, there is another problem that the conventional image readers require that the original 103 be placed not only facedown but also in a predetermined position, which entails cumbersome operation on the part of users.